Fig. 3

Topological incongruence and interspecific introgression. a Patterson’s D statistic values for the every trio of the seven species in the Prunella clade (eight taxa as P. o. ocularis and P. o. fagani were treated separately) that fall into the anomaly zone. The color legend is corresponding to the P value (Block-jackknife procedure to estimate P values) and magnitude of gene flow (D-statistic values). b Identifying possible introgression events using branch-specific statistic f_b (P3). The excess sharing of derived alleles between the branches of the tree is on the y-axis and species P3 on the x-axis. The ASTRAL species tree inferred from the genomic regions with low recombination rate was used as a guide tree in the analysis. Colors correspond to f_b values and asterisks denote block jackknifing significance at Z > 3 (FDR-adjusted P < 0.001). c Estimated proportions of introgression segments resulting from ancestral hybridization events